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Doug Steinbach

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Had the mag off - rebuilt one put back on.

Timing is close, but it impulses when the piston is about 1/2" before TDC. I know this cause I can stick my finger in the hole and feel it.

I've done what the manual says 3 times - just to make sure I had that right.

I assume I need to adjust the coupler bolts. Question is: since it is firing too soon for #1 - or possibly too late for #2 which way do I need to go?

I have the original mag off several times and never had this problem.

HELP!
 
Doug, Stay with #1 bring to TDC. Go to coupler and back it up 1 hole and try it again.
Go 1 hole at a time till it is correct.
By back it up opposite way that it turns.
If you mark with chaulk where you started it is good for reference. I would really like you to Email me the pictures of your starter set up. oldiron29
 
Doug,If you can find the flywheel mark I think it will be closer,Or bring the #1 to top dead center Loosen the drive and rotate it untill it clicks than put a bolt in the two holes that line up.

jimmy
 
James, Someone gave me an idea I wanted to bounce it off you. Have you ever seen or heard of an F-12 with a 12 volt Cub 154
starter/generator to work off the belt pully?
Oldiron29
 
When you checked it, did you have the mag lever all the way to "off" or full advance? If you didnt move the adjustmnent, then you shouldnt need to move it now. Are you sure its before TDC and not after TDC?
 
I did take the drive coupling off because it had one of the bolts broken off in it, so I decided to fix that. I also adjusted the valves while I had it down, so I did crank the engine over while it was off. I did finally the timing right, impulse trips just slightly after TDC.

I still the easy flooding problem, which it has had since I rebuilt it. I changed the carb out on it back at that time, sometime in Dec. I think. It floods really easy. Don't dare touch the joke. I have adjusted the float level some, to give it not so much gas, but to no avail.

If you have any good advice I'm all ears. It's starting to frustrate me, and right now I am at a loss.
 
Ok, here's just a thought.

My tractor has the piece that sticks up through hood on the fuel lines. I can blow through it, (which is what my dad always said to do to prime the fuel), it looks like fuel would come up the larger of the fuel lines, and inside this neck piece looks like it would overflow and fill the line to the carb. With the tractor running this should work just the opposite? Excess fuel from the pump would overflow to the larger line, and just return to the fuel line to the pump, at the tee located just behind the governor? Think this thing might be plugged up? The tractor sat for many years till I rebuilt it over the winter. All the fuel lines were trash, so it might make sense that this piece could be plugged too?, and causes the fuel pump to force the needle open and overflow the carb? Maybe????

I know the tractor runs cause I drove it 2 weeks ago, but since rebuilding it, it has been very hard to start. Most times I would have to pull it.
 
Doug you must adjust the mag with the bolts on the coupler off.Make sure you're at top dead on compression stroke.move mag so rotor is near but before the number one terminal. look at points turn mag with coupling bolts out until the points are just starting to open. At this point only two sets of holes will line up to replace the bolts .Find them and put in the bolts without moving mag. Another nate your elec start may turn too fast for the impulse to engage.
 
I put an extra gasket on the seat and seemed to stop my flooding problems.Seems like I did adjust it a couple of 32nds lower than what spec was too_One pull with the choke in, one with it out and if she dont fire then, then one more crank. i fought mine for 5 years to get it to start right, and it was worth the wait!
 
I did think about the starter cranking it too fast, and worried about that during the whole process of putting it on, , but I can hear the impulse snap when I crank it with the starter. The starter in reality doesn't turn it over near as fast as one would suspect it does. It's only 1.5 kw starter so it's not very powerful.

I timed the mag and engine according to the manual that I have, but as you suggest, in my mind I have been thinking that the rotor needed to be just ahead of #1 and not directly on it like the picture in my manual shows. Seems like if it impulses when the rotor is dead on, it would be too late as the impulse would fling it right past when it should be firing. I thought it needed to fling it right before firing, so it would fire on #1, and then move quickly to #3. But I may just be thinking too hard about, and out witting myself.

After I rebuilt the tractor from the hand crank to the PTO shaft, when I put the mag on it just cranked right up, so..... I either got lucky that time, or I am just missing something easy this time that I did the last time.
 
Doug,Ive heard of it,And Ive always wondered if it would work.The only reason I put a starter on my F14 is it was a hard starter since every thing was tight and I had 2 of the 3 parts,I actually enjoy cranking if the Tractor is right,I started my F12 the other day at 10 degrees and it had been sitting since fall and It fired the first crank,and idled after 2 more.

jimmy
 
Doug the impulse should really be disengaged when you do the timing so you're not fighting it trying to change where you want to set it. Remember the points just starting to open. On the flooding question one solution that works is as follows. Try to start briefly. If it doesn't start right up close the needle valve on the carb. turn it over and start it and return the needle valve to its original position. This is not a fix just a temporary solution till you figure out if the float is too high or the needle and seat dont hold or the screw is too far out to begin with or you have a week spark.
 
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